In his usual humorous self, Terence McKenna first describes his background, then shares his knowledge of plant-based psychoactive substances of the world and their impact on human culture.

McKenna discusses:
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Why are certain psychoactive plants cherished by some societies for millenia while others are ignored in spite of their safety and potency?

Why is our society and so many of its members neurotic, unhappy, and often dysfunctional? Why do we operate in a domain of limitation and misunderstanding?

Western society's discovery of psilocybin (magic) mushroom use by Mazatec people of Mexico in the 1950s. Why were Psilocybe species not discovered and/or used by shamans of the northwest United States?

What is the dose, route, and frequency that is best for plant use in spiritual practices?

​​Certain pharmacology was understood by Amazonian shamans centuries before Western medicine. Ayahuasca is a mix of two plants, one containing hallucinogenic DMT and the other containing an MAO inhibitor that allows the absorption of DMT in the gastrointestinal tract.

Which substance carries the risk of death by astonishment?​

What modern invention is the major illness of our current civilization?
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